package tr.edu.metu.is.mega.server.file;

import gwtupload.server.UploadAction;
import gwtupload.server.exceptions.UploadActionException;
import gwtupload.shared.UConsts;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Hashtable;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;

import tr.edu.metu.is.mega.client.resource.MegaConstants;

/**
 * Servlet to upload files to system.
 */
public class UploadServlet extends UploadAction {

    private static final long serialVersionUID = 1L;

    Hashtable<String, String> receivedContentTypes = new Hashtable<String, String>();

    /**
     * Maintain a list with received files and their content types.
     */
    Hashtable<String, File> receivedFiles = new Hashtable<String, File>();

    /**
     * {@inheritDoc}
     */
    @Override
    public String executeAction(HttpServletRequest request, List<FileItem> sessionFiles) throws UploadActionException {
        String response = "";
        for (FileItem item : sessionFiles) {
            if (false == item.isFormField()) {
                try {
                    String saveName = item.getName().replaceAll("[\\\\/><\\|\\s\"'{}()\\[\\]]+", "_");
                    String path = MegaConstants.DEPLOY_PATH + item.getFieldName().substring(0, item.getFieldName().lastIndexOf("/") + 1);
                    File file = new File(path);
                    file.mkdirs();

                    file = new File(path + saveName);

                    item.write(file);

                    // / Save a list with the received files
                    receivedFiles.put(item.getFieldName(), file);
                    receivedContentTypes.put(item.getFieldName(), item.getContentType());

                    // / Send a customized message to the client.
                    response = saveName;

                } catch (Exception e) {
                    throw new UploadActionException(e);
                }
            }
        }

        // / Remove files from session because we have a copy of them
        removeSessionFileItems(request);

        // / Send your customized message to the client.
        return response;
    }

    /**
     * Get the content of an uploaded file.
     */
    @Override
    public void getUploadedFile(HttpServletRequest request, HttpServletResponse response) throws IOException {
        String fieldName = request.getParameter(UConsts.PARAM_SHOW);
        File f = receivedFiles.get(fieldName);
        if (f != null) {
            response.setContentType(receivedContentTypes.get(fieldName));
            FileInputStream is = new FileInputStream(f);
            copyFromInputStreamToOutputStream(is, response.getOutputStream());
        } else {
            renderXmlResponse(request, response, XML_ERROR_ITEM_NOT_FOUND);
        }
    }

    /**
     * Remove a file when the user sends a delete request.
     */
    @Override
    public void removeItem(HttpServletRequest request, String fieldName) throws UploadActionException {
        File file = receivedFiles.get(fieldName);
        receivedFiles.remove(fieldName);
        receivedContentTypes.remove(fieldName);
        if (file != null) {
            file.delete();
        }
    }
}
